Hydraulic wheel



3 Sheets-Sheet 1 ll ll |lll D. L. RQTH HYDRAULIIIC WHEEL INVENI'OR.DONALD L. ROTH mm ATTYS.

Nov. 14, 1961 Filed March 7, 1958 D. L. ROTH Nov. 14, 1961 3Sheets-Sheet 2 wl/ A g United States Patent 071cc 3,008,424 HYDRAULICWHEEL Donald L. Roth, Uhrichsville, Ohio, assignor to MechanismsCompany, Uhrichsville, Ohio, a corporation of Ohio Filed Mar. 7, 1-958,Ser. No. 719,934

3 ms, (Cl.- DZ -lll) This invention relates to hydraulic wheels, andespecially to a wheel having a hydraulic transducer built therein foraction as either a hydraulic pump or motor depending upon the operatingconditions.

Heretofore there have been many diiferent types of hydraulic pump-s ormotors built wherein 'a stationary housing is provided that has ashaftmember iournalled therein for rotation by forces applied thereto byliquids supplied to the housing and flowing through sections of thehousing to provide desired rotary movement for the shaft and associatedmeans carried thereby. These prior types of hydraulic pumps or motorshave had wide commercial use and have been provided in many differentforms. However, there are uses for small hydraulic motors today whereinit would be desirable to have a stationary shaft with a rotor memberjournalled on the shaft and operated by hydraulic fluid supplied to thestationary shaft.

In some lift or carrier trucks used in industry today, there are smallsteering wheels which are driven by a motor connected thereto by anendless chain. Thus the wheel and drive motor must turn as a unit andrequire quite a bit of space for installation and operative clearance.

The general object of the present invention is to pro vide a novelhydraulic wheel with a hydraulic transducer built as a portion thereofand characterized by the use of a non-rotatable positioning shaft and'arotor housing in the hydraulic transducer.

Another object of the invention is to provide a hydraulic wheel ofrelatively small overall diameter wherein a hydraulic motor or pump isbuilt within the wheel construction and does not project from the Wheel.

Another object of the invention is to provide a hydraulic transducerwherein a plurality of radially extending vanes are carried by a rotorsleeve and are resiliently urged radially inwardly of the rotor sleevefor sealing engagement with an eccentric member fixedly carried by thepositioning shaft on which the rotor is journalled.

A further object of the invention is to provide .a hydraulic transducerof the class described wherein coil springs of greater diameter than thewidth of vane receiving slots are provided in the rotor for urging thevanes in the pump radially inwardly thereof.

Another object of the invention is to provide a support shaft in atransducer of the type described wherein two oil or other liquid passagebores are provided in the shaft so that fluid ports can be providedtherein by diametrically extending holes connecting to the shaft boresand axially offset from each other but with each diametrically extendinghole providing two discharge or inlet ports for the oil passage bore towhich it connects.

Further objects of the invention are to provide a control cam on astationary shaft and with bore means being provided in the stationaryshaft and control cam for flow of liquids therethrough and wherein thecontrol cam is secured to the stationary shaft means by longitudinallysplit spring sleeves which lock the cam to the shaft and at the sametime provide center bores for liquid transmission or flow therethrough;to provide a hydraulic wheel wherein the wheel can be turned through 360without any limitation on the rotary movement thereof by fluid connectorlines or the like; to provide fluid receiving and distributing bores inparallel relationship toeach other v Patented Nov. 14, 1361 in astationary-shaft but offset fromthe center thereof to permit theprovision of diametrically positioned distributing bores in thestationary shaft and corresponding diametrically opposed pressure zonesin the pump or motor; to provide radially movable vanes extendingradially in wardly of the rotor in a hydraulic transducer and whereinthe high pressure liquid in the pump exerts a radially inwardly directedforce against the vanes; and to provide a hydraulic transducer builtinto a small wheel.

The foregoing and other objects and advantages of the invention will bemade more apparent as the specification proceeds.

When referring to corresponding parts shown in the drawings and referredto in the specification, corresponding numerals are used to facilitatecomparison between such corresponding parts. a

A currently preferred embodiment of the present in- Vention is shown inthe accompanyingdrawings, wherein:

FIG. 1 is a vertical section through a hydraulic, or transducer wheelembodying the principles of the invention;

FIGS. 2 and 3 are vertical sections taken on lines 2-Z and 3-3 of FIG.1;

FIG. 4 is an enlarged fragmentary section showing the sealing action ofa vane in the pumping chamber of the hydraulic wheel of the invention; 7

FIG. 5 is a fragmentary section showing the construction and positioningof a slightly modified vane assembly in the hydraulic wheel of theinvention;

FIG. 6 is a plan of a portion of the hydraulic wheel of the inventiontaken on line 6--6 of FIG. 5;

FIG. 7 is a vertical section, like FIG. 2, taken of a modifiedtransducer of the invention and FIG. 8 is a fragmentary section, similarto FIG. 5, of

a further modification of the invention.

The invention generally relates to a hydraulic transducer comprising apositioning shaft having a pair of parallel bores therein offset fromthe center axis thereof, support means connected to the shaft toposition it, which support means have a pair of bores therein connectedto the bores in the shaft for flow of liquid to and from the shaft, acam secured to and carried by the shaft, which cam has circumferentiallyextending fluid distributing recesses provided in the periphery thereofat circumferentially spaced portions thereof and individually connectedto one of the bores in the positioning shaft, a rotor journalled on theshaft and encompassing the cam, a plurality of vauesmeceived in slots inthe rotor for sliding engagement with the cam,.and spring means betweenthe rotor and the vanes to urge the vanes radially inwardly against saidcam and provide a rotatable unit on a stationary shaft coupled byhydraulic chamber means.

The improved hydraulic transducer of the invention is adapted for useeither. as a motor when hydraulic pres sure liquid is supplied theretoin order to drive a hydraulic wheel into which the transducer is built,or else the transducer could be used as a pump to force liquid therefromshould the wheel, orvehiclc on which the Wheel is positioned be drivenby another power s urce.

In this currently preferred embodiment of the inven tion, itis'illustrated'in. a hydraulic wheel, indicated as a whole by thenumeral 1. Such hydraulic wheel 1 includes a positioning, or supportshaft 2 on which a wheel 3 is suitably journalled for rotary action. Theshaft 2 is secured to and positioned by an elbow 4 'at one end thereofand with the elbow 4 extending to and being secured to a Means areprovided for a controlled flow of pressure liquid to and from the wheel3 and to this end, a pair of separate conduits or bores 7 and 8 areprovided in the sleeve 6 and with each such bore 7 or 8 being connectedto an individual annular connection groove 9 or 10, respectively,provided in axially spaced portions of the periphery of the swivel stemThe swivel stem 5 likewise has a pair of axially extending bores 11 and12 connecting, respectively to the grooves 9 and for flow of pressureliquid to and from the swivel stem 5 and to the elbow 4- connectedthereto. Such elbow 4 likewise has a pair of parallel, but individual,bores 13 and 13a provided therein and permanently connecting to thebores 11 and 12, respectively, and the stern 5 for transmitting pressurefluid to a pair of parallel bores, or passages 14 and 15, respectively,provided in the shaft 2. The bores 14 and 15 preferably are spacedradially from the center axis of the shaft 2 and are spacedcircumferentially from each other as best shown in FIG. 2.

The shaft 2 has a cam or eccentric 16 suitably secured thereto and thiscam 16 has a plurality of liquid distributing recesses 17 extendingalong portions of the periphery thereof and with a pair of such recesses17, 17 being shown formed in diametrically opposed portions of the cam16. A diametrically extending bore 18 is provided in the shaft 2 andconnects the recesses 17 to the bore 14 in the shaft 2. The bore 18extends through both the shaft 2 and the cam 16 and a similar, butcircumferentially spaced series of recesses 19 is provided in an axiallyspaced portion of the cam 16 from that at which the section shown inFIG. 3 is taken. The recesses 19 are connected by a diametricallyextending bore 20 provided in a portion of the shaft 2 and cam 16 spacedaxially from the bore 18. Such bore 20 connects to the other axial bore15 in the shaft 2. Portions of the periphery of the cam 16 indicated at16a are of arcuate contour and are snugly received within a rotor 21 forno flow of liquid in that portion of the cam, and for no pumping actiontherein. The portions of the bores 18 and 20 formed in the shaft 2 formextension bores that connect the passages, or bores 14 and 15 to theperiphery of the shaft 2. The recesses 17 and 19 are formed inperipheral portions of the cam 16 intermediate the arcuate sections 1611of the cam surface.

It is an important feature of the invention that the rotor 21encompasses and encloses the surfaces of the cam 16 and with the rotor21 being positioned on the shaft 2 for rotation with relation thereto.Thus a pair of end plates 22 and 23 are secured to the rotor 21, as bymeans of bolts 24, to provide an integral unit for rotary action on theshaft 2 as by means of bearings 25. Suitable O-rings, or similar packingmeans 26, are carried by the end plates 22 and 23 to seal the rotor 21with relation to the shaft 2 and associated means. Thus a pumping orpressure chamber 27 is provided intermediate the surfaces of the cam 16and associated rotor 21 and end plates 22 and 23.

For the actual pumping or hydraulic motor action in this chamber 27, aplurality of axially extending vane means 28 are positioned in recesses29 provided'in the rotor 21. Such vanes 28 preferably are of the lengthof the cam 16, as shown in FIG. 4 of the drawings. Normally such vanes28 each have at least a pair of recesses 28a extending radiallythereinto from the radially outer end thereof. Such recesses, as shownin FIGS. 4 and 5, are adapted to receive suitable spring means, such ascoil springs 30, to compress such coil springs against the innerperiphery of the rotor 21 whereby the vanes 28 are resiliently urgedradially inwardly of the hydraulic wheel 1 of the invention by thesprings to bear against the periphery of the cam 16. Normally theradially inner surfaces of these vanes 28 are of arcuate shapeto-provide a smooth bearing engagement between the vane and cam surface.

It should be noted that the recesses 29 provided in the rotor 21 areslightly larger in a circumferential direction than the width of thevanes 28 so that the vanes are loosely positioned. Such looseness of thevanes in their receiving recesses permits them to tilt or cant slightlyin the recess by the pressures exerted thereon by liquid being pumped,for example through the supply bores to the chamber 27. FIG. 4 of thedrawings clearly brings out the fact that the high pressure supplied tothe chamber 27 can flow into and through the recesses 29 to exert highpressure against one side and the radially outer surface of the vanes 28and urge such vanes radially inwardly of the hydraulic transducer. Thisaids in effecting a tight seal of the vanes against the cam and theopposite or low pressure wall of the recess 29 in which the vanes 28 arepositioned.

FIG. 3 of the drawings clearly brings out the fact that the vanes 28 aremore closely spaced circumferentially of the rotor 21 than the distanceintermediate the adjacent sets of fluid distributing or receivingrecesses 17 and 19 provided in the cam 16. Thus at least a pair ofclosed, but movable, pressure chambers are made within a part of thechamber 27 at all times and with such pressure being exerted upon two ormore of the vanes 28 to urge the rotor 21 to rotate sufficiently as topermit fluid in such pressure chambers to reach the next set ofrecesses, such as the recesses 19, for flow of the pressure liquid fromthe chamber 27 after the driving action, for example, has been effected.

Referring now to the structure shown in FIG. 3 of the drawings, itshould be noted that a longitudinally split sleeve 32 is used forsecuring the cam 16 to the shaft 2. One of the split sleeves 32 isreceived in each of the diametrically extending bores 18 and 20 providedin the shaft 2 and with the sleeve extending into the portion of thebore provided in the cam 16. Thus the split sleeve holds the cam to theshaft but at the same time has a hollow bore for transmission ofpressure fluid therethrough. Hence, no key or other member is requiredto secure the cam 16 to its positioning shaft and this simplifies andimproves the construction of the transducer of the invention.

The hydraulic wheel of the invention is completed by use of conventionalmembers and a suitable felloe or rim 33 is secured to the rotor 21 andforms an integral unit therewith. Any desired type of tread member 34,usually made from rubber or similar material, is secured to the rim 33.

The drawing clearly shows that the tread member 34 and rim 33 arecentered on the cam 16 and that this wheel 3 is of relatively smalldiameter but has effective pumping or transducing members providedwithin the periphery of the rim 33.

FIGS. 5 and *6 of the drawings show that, if desired, holes 100 areformed in the rotor 21a in which coil springs 31a are positioned can bewider in circumferential length than the widths of vanes 28a so thatsuch coil springs 310 are received in recesses 128a in the vanes 28a.The holes 100 have sections that extend into the adjacent faces of thewalls defining recesses 29a in the rotor 21. Hence, the effectivediameter of the coil springs 31a is not limited to the circumferentialwidth of the vanes 28a or the recesses 29a. The springs 31a can bepositioned before the rotor 21a is pressed into its rim 33a, or they canbe tilted and be fed into the holes 100 through the recesses 29a. 7

A modified type of a hydraulic transducer of the invention is shown inFIG. 7 of the drawings and in this instance, a stationary shaft 2b isshown which has a pair of axially extending bores 14b and 15b providedtherein.

These bores 14b and 15b connect to diametrically opposed distributinggrooves or recesses 17b and 19b provided in a cam or eccentric 16bsuitably secured to the shaft 2b. Such distributing recesses 17b and 19bcan be of relatively long circumferential extent and define only onepumping chamber or section adjacent the periphery of the cam 16b.Suitable vanes 28b are positioned in a rotor 21b like that shown in theother iigures of the drawings so that in this embodiment of theinvention, fluid can flow out of the bore 14b through the distributingrecess 17b and associated discharge port 140 of the bore 14b forpressure action against the vanes 28b to urge them to rotate in counterclockwise direction and carry the rotor 21b therewith. When anyindividual vane 28b reaches the first circumferential portion of therecess 19b, then fluid starts to flow from the actual pumping chambertowards the discharge bore 15b through the connecting section 150provided in the shaft 2b and connecting to the recess 19b.

It thus will be seen that in the embodiment of the invention shown inFIG. 7, the pressure fluid flows into the pumping chamber 27b along onerelatively long circumferential portion thereof, and that only oneexhaust port is provided for flow of pressure liquid from this pumpingchamber.

FIG. 8 shows a further modification of the invention wherein a rotor2112 has several spaced holes formed therein aligned with each slot 2%provided in the radially inner edge of the rotor. These holes are oflarger diameter than the width of the slot 29b which receives a vane 28btherein for operative engagement with the cam 16b. Springs 31b arereceived in these holes limb to urge the vane 28b out for operativeengagement with the cam 16b. The outer ends of the holes limb are closedby means of the rim member 3312 provided in this embodiment of theinvention. It will be noted that the slot 2% provides a continuous edgesurface for sealing action with the vane 28b as tilted by pressureliquid flowing into engagement with the radially outer end of the vane28b and urging it into tight engagement with the cam 16b.

Transducers or hydraulic Wheels of the invention have been constructedand have given very satisfactory action. Any suitable supply of pressureliquid can be connected to the swivel sleeve 6 to drive the wheel 3 byuse of the transducer as a motor, or if the wheel 3' is otherwisedriven, the transducer functions as a pump to provide pressure liquid atthe swivel sleeve 6.

The wheel 3 is compact and functions effectively for the purposesstated. The rotor 21 can be driven by the pressure liquid supplied bythe stationary shaft on which it is journalled so that the objects ofthe invention are thought to be achieved.

While several complete embodiments of the invention have been disclosedherein, it will be appreciated that modification of these particularembodiments of the invention may be resorted to without departing fromthe scope of the invention as defined in the appended claims.

What is claimed is:

1. A hydraulic transducer comprising a positioning shaft having a pairof parallel bores therein offset from the center axis thereof, a camcarried by said shaft, said cam having circumferentially extending fluiddistributing recesses provided in the periphery thereof atcircumferentially spaced portions thereof and individually connected toone of said bores in said positioning shaft, said cam and shaft having apair of diametrically extending bores therein individually connectingsaid parallel bores to different ones of said fluid distributingrecesses, a longitudinally split sleeve positioned in each of saiddiametrically extending bores to secure said cam to said shaft but topermit pressure liquid flow therethrough, a rotor journalled on saidshaft and encompassing said cam, said rotor having slots in a radiallyinner surface thereof, a plurality of vanes received in said slots insaid rotor for sliding engagement with said cam, and spring meansbetween said rotor and said vanes to urge said vanes radially inwardlyagainst said cam.

2. A hydraulic transducer comprising a positioning shaft having a pairof parallel bores therein offset from the center axis thereof, a camstationarily carried by said shaft, said cam having circumferentiallyextending fluid distributing recesses provided in the periphery thereofat circumferentially spaced portions thereof and individually connectedto one of said bores in said positioning shaft, said cam and shafthaving a pair of diametrically extending bores therein individuallyconnecting said parallel bores to different ones of said fluiddistributing recesses, a longitudinally split sleeve positioned in eachof said diametrically extending bores to secure said cam to said shaftbut to permit pressure liquid flow therethrough, a slotted rotorjournalled on said shaft and encompassing said cam, a plurality of vanesreceived in said slots in said rotor and protruding therefrom forsliding engagement with said cam, said vanes having slots extendingthereinto from the radially outer ends thereof and being looselyreceived in but contacting both walls of said rotor slots for flow ofpressure liquid against one side face and the radially outer end of saidvanes, and spring means be-.

tween said rotor and said vanes to urge said vanes radially inwardlyagainst said cam.

3. A hydraulic transducer comprising a stationary axle having twoaxially extending fluid passages therein and connecting to the axleperiphery by passage extensions, a tubular lobed cam having twoperipheral circumferentially spaced porting recesses per lobestationarily secured to said axle and substantially radially extendingbores formed therein and connecting said recesses re spectively to saidpassage extensions in said axle for hydraulic flow to and from said cam,a ring rotor journalled on said axle, vanes carried by said ring rotor,and resilient means operatively carried by said ring rotor urging saidvanes inward against the periphery of said cam for continuous sealingengagement therewith, the circumferential distance between adjacentvanes being less than the circumferential distance between portingrecesses in said cam, said rotor having individual closed radially outerend vane receiving slots therein in its radially inner surface, saidvanes being loosely received in said slots and being tilted in saidslots by hydraulic pressure applied thereto to seal against an edge ofsaid slot remote from the source of pressure liquid, said vanes and saidslots being correlated in size so that said vanes contact both walls ofsaid Slots when tilted, said vanes having uniform size recessesextending into the radially outer ends thereof the entirecircumferential width thereof for uniform flow of pressure liquid atfull pressure into said slot and pasta said vane through the saidrecesses therein to contact the radially outer end of said vanesregardless of the radial position of a said vane in a said slot.

4. A hydraulic transducer as in claim 3 in which said cam has two lobesand the tWo fluid passages in said axle are eccentrically located withrelation to the axis of said axle so that each pair of porting recessesin the cam is inter-connected and is connected to its respective fluidpassage by a straight radially extending hole at a different axiallocation in said' axle.

5. A hydraulic transducer comprising a stationary axle having twoaxially extending fluid passages therein and connecting to the axleperiphery by passage extensions, a tubular lobed cam having twoperipheral circumferentially spaced porting recesses per lobestationarily secured to said axle and having radially extending boresconnecting said recesses individually to said passages in said axle, aring rotor journalled on said axle, vanes carried by said ring rotor,and coil springs operatively carried by said ring rotor urging saidvanes radially inwardly against the periphery of said cam for continuoussealing engagement therewith, the circumferential distance be tweenadjacent vanes being less than the circumferential distance betweenporting recesses in said cam, said rotor having individual closedradially outer end vane receiving slots therein in its radially innersurface, said vanes being loosely received in said slots and beingtilted in said slots by hydraulic pressure applied thereto to sealagainst an edge of said slot remote from the source of pressure liquid,said vanes and said slots being correlated in size so that said vanescontact both walls of said slots when tilted, said ring rotor havingcoil spring receiving means provided therein wider than thecircumferential Width of said slots extending thereinto from theradially outer end portion thereof and extending radially inwardly ofthe radially outer ends of saidvanes for uniform flow of pressure liquidat full pressure into said slot and past a said vane through the coilspring receiving means to contact the radially outer end of said vanesregardless of the radial position of a said vane in a said slot.

6. A hydraulic transducer comprising a stationary axle having twoaxially extending fluid passages therein and radially extendingextension bores connecting such fluid passageways to the periphery ofsaid axle, an eccentric sleeve having two lobes thereon rigidlyand'stationarily supported on said axle and provided with two pairs ofcircumferentially spaced porting recesses in its outer periphery, saideccentric having radially extending bores therein extending to its innerperiphery to connect each of said pairs of recesses to One of saidextension bores of said two fluid passages in said axle, a ring rotorjournalled on said axle, vanes carried by said ring rotor, and resilientmeans engaging said vanes and urging said vanes inwardly against theperiphery of said eccentric sleeve, the circumferential distance betweenadjacent vanes being less than the circumferential distance between saidporting recesses in said eccentric sleeve, each of said bores beingradially aligned with one of said extension bores, said extension boresbeing at diiferent axial locations in said axle, and a hollow pinpositioned in at least one of said bores and its aligned extension boreto permit fluid flow therethrough and to secure said eccentric sleeve tosaid axle.

7. A hydraulic transducer comprising a stationary axle having a pair ofaxially extending passages therein and having extension bores thereinconnecting said passages to the periphery of said axle, a tubulareccentric having at least one cam lobe thereon rigidly and stationarilysupported on said axle and provided with two peripheralcircumferentially spaced porting recesses per cam lobe therein, saideccentric having individual bores therein extending from said portingrecesses to the inner periphery of said eccentric to connect to saidextension bores, a ring rotor journalled on said axle and having slotsin its inner surface, vanes carried in said slots in said ring rotor andslidably engaging said eccentric, said vanes being parallel with theaxis of said axle and being smaller in circumferential width than saidslots, said ring rotor having apertures therein of greater diameter thanthe circumferential width of said slots and extending from the radiallyouter periphery of said ring rotor to connect to said slots butterminating spaced from the radially inner ends thereof, a rim engagingthe periphery of said ring rotor and sealing the outer ends of saidapertures, said apertures extending a distance past the radially outerends of said vanes to provide passageways for hydraulic fluid into saidslots for application of full transducer fluid pressure to the radiallyouter ends of said vanes, and resilient means engaging said vanes andsaid rim to urge said vanes inwardly against the periphery of saideccentric, the circumferential distance between adjacent vanes beingless than the circumferential distance between said porting recesses insaid eccentric.

' 8. A hydraulic transducer comprising a stationary axle having twoaxially extending fluid passages therein, an eccentric sleeve rigidlyand stationarily supported on said axle and provided with at least twoperipheral circumferentially spaced porting recesses therein, saideccentric sleeve having individual bores therein connecting said portingrecesses to the inner periphery of said sleeve, said axle having boreextensions therein connecting said fluid passages to the periphery ofsaid axle, said bores connecting respectively to said bore extensions ofsaid two fluid passages in said axle, a ring rotor journalled on saidaxle to form a pressure chamber around said eccentric sleeve and havingaxially extending slots in its inner surface, vanes carried in but beingcircumferentially narrower than said slots in said ring rotor andslidably engaging said eccentric sleeve, said vanes being parallel withthe axis of said axle and being tilted in use by the hydraulic fluid inthe transducer to engage both walls of the said slot in which it ispositioned, said ring rotor having at least an aperture therein locatedat each said slot and of greater diameter than the circumferential widthof said slots and extending from the radially outer periphery of saidring rotor nearly to the radially inner ends of said slots, saidapertures extending a distance past the radially outer ends of saidvanes to provide passageways for hydraulic fluid into said slots forapplication of full transducer fluid pressure to the radially outer endsof said vanes, a rim engaging the periphery of and carried by said ringrotor to seal the radially outer ends of said apertures, and a coilspring positioned in each of said apertures and engaging said vanes andsaid rim to urge said vanes inwardly against the periphery of saideccentric sleeve, the circumferential distance between the adjacentvanes being less than the circumferential distance between said portingrecesses in said eccentric sleeve, said apertures aiding the flow ofliquid from the pressure chamber to the radially outer surfaces of saidvanes.

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